Felt hardening machine



Nov. 4, 1952 R. l. ROBBINS ETAL 2,616,152

FELT HARDENING MACHINE 5 Sheets-Sheet 1 Filed Sept. 8, 1950 6 Ralph I liobms Bela fieyer INVENTOR:

Nov. 4, 1952 R. 1. ROBBINS ETAL 2,516,152

FELT HARDENING MACHINE Filed Sept. 8, 1950 5 Sheets-Sheet 2 mm mm mm mm g 3 m S m w. m N M br M w mm R .3 .m. 3 I v In lPh w 0e RB if w mm KN Nov. 4, 1952 R. ROBBINS EI'AL FELT HARDENING MACHINE 5 Sheets-Sheet 3 Filed Sept. 8, 1950 Fig. 4

Rel pf; Z. 3066/05 4i m J M m am 9m 2. M W m B Nov. 4, 1952 R. l. ROBBINS ETAL 2,616,152

FELT HARDENING MAQHINE Filed Sept. 8, 1950 5 Sheets-Sheet 4 2o ll-ll Fig.7 I

a 57 as as as as as as as as a: 3/ 3! 3l 3! 3l 3! 31 a:

Fig. 6

Ralph I flabby/5 l Be/a fieyer INVENTORS Nov. 4, 1952 v R. 1. RfSBBI S EI'AL 2,616,152

FELT HARDENING MACHINE 5 Sheets-Sheet 5 Filed Sept. 8, 1950 Rab I I. fobbins Bela fieyer INVENTORJ' r 3 5 64 w, m BY 1/ T 7 7 Patented Nov. 4, 1952 UNITED STATES "LOiF F-ICE .dtobb ins, 'iAndover, Mass and Bela .;.Frey .er, :Gornwalleon-Hu dson, NHYH iassignors .t o l meriean lifelt Qompai1y; (llenyill'ei(7.5113 .a a

iehrp'oration 'of Massachusetts ipplication"September s, mgksaalmama '4 .Claims.

, invention :relatesjito improvements inielt hardener machines. l p x In the -process of makingfelt; the'wo'ol or other ffibnes zar gcarded :and rmiltip'les of the resulting websarecombined to 'aifelt'hatt. Ihi'sEhatt maycon'sist of 'iany" 'desiried thickness "of carded fibres or webs joined all in the samenirection, "such as lengthwise lei the piece. :01: in different on sation-s, 'such as crosswisef-of and lengthwise or the piece. [The resultant zbatt'is :a'piece o'f material in which "the webs have been 'joined "but, which Elias praeticallyno tensile streng'th "because the fibres comprising the individual webs haile :notybeen intermingled rand interjoined "of makingtfelt. is ito cause these ffibres :to intermingle and interjoin to zferm'a. liomeogeneous relatively "solid and strong piece' of .materiali en- 'erally termed in the :art :as a hardened batt :or nnfulled itelt. The IDHQCESS ofpm'ranstorming the iw-rela'tively ':=ili-msy bat't into :fithe stronger :more

;*densely packed abatt is commonly knownfin the .art as hardeningi an'd is accomplished sbylisubj ect- Ying the batt to 'pressura' ghea't and moisture *while at the .same time fapply-ing i-ltov :it :a reciprocating pr vibratory motion which may. be rotary aor :may "betransverseio'the'length of 'theibatt. U v

"In commercial--.prao1ticetwo t pes of manhines ihave "been :employed "(to perform this 'liardenin'g f yardage :felts. v

One type, which may be termed :a platen hardener, comprises a. bed arranged to =-supp crt j and "a relatively, rheauyggalate inlay zbe low'ere'd ton "that section, f :the and pressed down ithereupim rat the @same timeymovin' 5m 1 reciprbcatory manner either in a ';;direction back continuously if jb weninnultiple;

gs i fjf ct'eaitopr ss ciprocatory ot'ron.

. has van nbyious -aduantagelover the platen type ginlbeing continuous in operation, its history in elartis not one Oi success. From time to time ls ince its jintroduetiun, attempted improvements ,haxebeen rmade i-n its design and construction andjlf elt manufacturers have eagerly installed the fimproved? roller machines 01111 11130 find that the problem of satisfactory operation has not 0 beengsolved and ,to abandon the new roller machines for the ield intermittent operating platen machines, lorlatbes't "to use the roller machines only as an adjunctfto the platen machine.

Amon 12 9 most serious difiicul ties that have been "encountered in the/use of roller ,hardener machines for yardage felts inihepast have been j the unevenguality of felt produced, the failure jt'o accomplish"suffiqientfhardeningjin one run and the -'a't 'tendant necessity of [running the felt 'jthrou'gh "the ha ene several times, inability to harden morethan onefbattat at'ime, and maintenance problems fgenera'llycaused by excessive vibration resulting in wear of the operating parts "such as "the rollefrs thus exaggerating the .defect "of producing yardage felt of uneven quality.

a In general it is among theo'bjectsof the present invention to provide {a felt roller hardener machine for yardage felts-in which "the above mentioned disadvantages and defects are overcome and to provide a practical -felt roller hardener machine which' i's' capable of producing a product of even quality' in a continuous manner .at a high rate of production' and which is designed to "minimize" operating and maintenance difficulties.

More specifically' amon'g the objects and advantages of this invention are:

*To zprovide a 'ro'ller hardener 'machine which -"-is capabl'e of "increased hardening efficiency "over the felt hardeners of the prior art;

. *Tomrovide airoll'er hardener machine in which full v'k'r idt-h baits can 'be successfully hardened by the machine at a greatly increased speed over those o'f the prior art;

1 To provide "a roller hardener -machine "through V which a plurality of separate batts can be" passed and successfully hardened simultaneously;

a proyid'e a rollerthardener -nfa chine in which adj ustm'ents' may be readily made for the satisfactory hardening of batts' of varying -thicknesses 1T0 prdvide' a roller hardner machine' in w hich ;ithe;-:-batt;to be hardened is 'conveyed bjy means of ;.-i"endless isconveyor aprons or otherwise through ,fafset of rollers, "each set comprising a plurality o'f rupperrollers and a plurality of lower rollers,

hydraulic force operating vertically on the lower rollers in an upward direction;

To provide a roller hardener machine in which the upper rollers move in a reciprocating manner in a direction parallel to their axes and in which said rollers are positively locked against any motion in any other direction except rotation about their respective axes;

To provide a roller hardener machine in which the rollers are incapable of rocking;

To provide a roller hardener machine in which the upper rollers are locked against vertical displacement; I

To provide a roller hardener machine in which the upper rollers are free to revolve about their respective aXes and which includes means for reciprocating said rollers in a direction parallel to their axes and in which the lower rollers are driven to move conveyor aprons but cannot move in a direction parallel to their axes;

To provide in a roller hardener machine improved means for jointly and selectively varying the pressure applied to the batt, the amplitude of the reciprocatory motion of the upper rollers parallel to their axes, the speed of said reciprocation of the upper rollers, and the speed of rotation of the lower rollers driving the conveyor aprons;

These and other features and objects of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof selected for purposes of illustration and shown in the accompanying drawings.

The invention accordingly consists in the features of construction, combination of elements and arrangement of parts as will be exemplified in the construction hereinafter described and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings:

Fig. 1 is a plan view of a machine embodying the invention showing a portion of the feeding and receiving tables;

Fig. 2 is an elevation of the machine of Fig. 1 viewed from the receiving end with a modification in the arrangement of the motors for the reciprocating drive;

Fig. 3 is a cross-sectional view on the line 3-3 of Fig. 2 looking in the direction of the arrows; Fig.4 is a cross-sectional'view on the line 4-4 of Fig. 2 looking in the direction of the arrows with certain parts cut away;

Fig. 5 is a cross-sectional view on the line 55 of Fig. 4 looking in the direction of the arrows; Fig. 6 is a cross-sectional view on the line 6-6 of Fig. 1 looking in the direction of the arrows; Fig. '7 is a diagrammatic showing of the lower rollers adapted to be used in the machine of Fig. 1

. and suitable means for driving the same;

Fig. 8 is a fragmentary section on an enlarged scale cut longitudinally through one of the rollers;

Fig. 9 is an elevation showing the oscillating yoke with compensating springs and weight attached thereto for the embodiment of Fig. 1;

Fig. 10 is a detail showing of one of the compensating springs of Fig. 9 and its connections to the yoke and compensating weight;

Fig. ll-is a cross-section on the line Il--H of Fig. 9 looking in the direction of the arrows; and

Fig. 12 is a schematic drawing showing an arrangement of the machine of Fig. 1. in comb i-' 4 nation with parts used to handle the material set up for one mode of operation.

Essentially the machine is made up of one or more units of upper 20 and lower 2! rollers between which the material to be hardened is fed. In the embodiment shown in the drawings, as

may readily be seen from Figs; 1 and 2, the machine comprises two units each of which has four upper and five lower rollers. It is to be understood, however, that the machine may comprise but one unit or as many units as is desired for the circumstances under which it is used. It is advantageous, however, for some aspects of the invention'that each unit comprise an even number of pairs of upper rollers, that is, a minimum of nine rollers.

The frame 22 of the machine is firmly mounted on substantial foundations 23 as is clearly shown in Fig. 2 and, as shown in Fig. 1, has mounted adjacent to it a feeding table 24 and a receivingitable 25. The various prime movers, clutches, brakes and other driving mechanisms all of which will be described more in detail hereinbelow may be mounted on separate foundations or, if desired, upon a foundation or base made integral with that for the main part of the machine. I

The housings 26 for the bearings for upper rollers 20 are mounted on frame 22 by means of bearing blocks 21. As is shown in Fig. 1, the shafts 28 of upper rollers 20 extend at one" of their ends beyond bearing housings 26 into thrust bearings/enclosed in thrust bearing housings 29 which, as is more fully described hereinbelow, impart a reciprocating longitudinal motion to the upper rollers 20 to which they are connected. Thrust bearing housings 29 are arranged so that the ones for alternate upper rollers 20 are on the same side of frame 22.

As is most readily seen in Figs. 4 and 5 bearing's 30 for shafts 3| of lower rollers 21 are mounted in yokes 32 which are moveable in an up and down direction by piston rods 33 attached to pistons of pneumatic cylinders 35 in a manner to be described hereinbelow. Lower rollers 2| are rotated about their respective axes by common driving means which may be a series of belts or chains 36 as is shown diagrammatically in Fig. 7, driven from a shaft 37 in turn driven by a motor or other prime mover 38. It is to be understood that any driving arrangement which drives all of lower rollers 25 in the same direction and at the same speeds may be substituted for the arrangement shown in Fig. 7. In the arrangement Shown in Fig. 7, one ofthe receiving table rollers 39 is mounted on shaft 37.

The material F to be'hardened passes between the sets of upper rollers 20 and lower rollers 2| in a direction from, say left to right, as shown in Figs. 1, 3 and 12 and right to left as viewed in Fig. 4. Material F is carried on a conveyer apron B which passes through the machine and between the upper and lower rollers. In some instances it may be desirable to run the material F through the machine between two conveyor aprons, an upper apron and a lower apron. As has been previously stated one of the essential operations on the material to harden it is to exert pressure on it. The means for accomplishing this in the embodiment of the invention herein described is best shown in relation to Figs. 4 and 5. Each shaft 3! of lower rollers 2| is r0- tatably held in a bearing 30 which in turn is mounted in a yoke 32. Yokes 32 are free to slide up and down but are prevented from any lateral rare-reins 5 :euide ;4 hi arm-m chined to r i ermi 1idabl i m ionmf thereup =rsi ee e 19 kes. 3.2 ,an which are cast-integrallyr'witlronotherwisexfirmlyiatta h iztcxupp roller bearingblock .21. Pneumaticzor :hydraulic i cylinders 35 mounted on upper ,roller bearing block 21;;are connected by any suitable means .ssuchas aby in1et.connection 11.4 I :to :a source a (not shown) .-of.;fiuid .under relatively high =-,pressurel :Pmferably .the .pressure of gthe .-fiuid.:;may.:be --r.egulated. .Pneumatic --,-pist,ons 34 rare slideably mounted; incylinders 13.5 zformingepressure; chambers :42: below the pistons. Pistons :34: are each respectively. attached to piston, rods .33 which :eX- .tend through properly packed.v apertures in .the --bo.ttom of. cylinders=.35 provided:for:.thate;purpose. azyokeszzfl are connected. respec.tivel-y::to;the other .en'ds ofipistonrods 33. -:It is.:obviousi-fromt the above description .thattvhen the Jfluidepressure -pistonirods .133; yokes'1'32'.:and' shafts 13!. of 1 lower -rollersi2 leareiurged upward :with:-the:-result,.-. since upper rollers :28, although freeto' oscillateilongitu dinallyand .to rotate, arev otherwisefixed; the pressure on material F between .upper..=rollers+20 and lower rollers2 I is increased.

The mechanism and arrangement of partsto :cause :upper rollers .20 vto oscillate -along their respective .-.axes a; is =.-most readily described with -relation to-Figs. 1,x2 and'6. Referring specifically @to Fig. :1, a motoror other suitable prime mover '43 drives, -through.chain or belt -44, hydraulic coupling 45, gear assembly 46 and chainorbelt 4'l,- shait- 4fi.' :Rotatablymounted on shaftAB is eccentr-ic crank :49 which translates the rotary motion of shaft 43 to a reciprocatory motion given oscillating yoke 50 to which it is pivoted as is more clearly shown'in Figs. B and lland aswill be described in more detail hereinbelow. Each-oscillating-yoke 59 isattached to ormay be made integraliwith --a thrust bearing-housing -29-for the'shaftsifiof apair of upper rollers I which are {disposed in an alternate manner-with other upper rollersZD. Thus as is shown in-Fig. 1.,"f01 a unit comprisingfourupperirollersi-fl, one-yoke 50 oscillates or reciprocates thesecond and fourth upper rollers "2i! and a second yoke -5l oscillates -or-reciprocates the first andthir'd 'upper rollers 28 all reading from the left to'right.

Oscillating yoke '51 may be driven 1 by "motor-'43 through chain "or belt -45, hydraulic coupling -45,

gear assembly 46, ;shaft 5-2 coupled at-e-ach-end "by flexible-couplings 53 and passing to theother side of the =nrachine, ear assembly 1 54, "transmission belt or chain-55, eccentric shaft Edand eccentric crank 5?. 'S ince 'it is desiredtohave adjacent pairs f-upper rollers 2i! of aunit-oscillate 180 out of fphase, there is an advantage "from 'the sta-ndpoint -01 regulation to drive eaeh pair from a common source of power. However, 'in some instances it-may prove'advantageous to drive eachpair separately as by a. second motor "58, as shownin the modification of Fig. 2, and =t p provideregulatin g, means to keep the reciproeation gf each pair 1180 out of =phase. fMounteld :on eccentric shafts 48 and 56 1s a conventional -magnetic brake 59 the function of which will be explained hereinbelow where themode o'f-operation of the machine is described.

fteferringspecificallyto Figs. 1,2,9 and Hit may-be seen that-eccentric cranks 49 and 5-! pass through apertures 60 in compensating weights '6! -:Which--are mounted on base 23 by means of resilient supports 62. -Supports -62 may bezmade of strips of :micarta'or any other suitable main pressure chambers 42 is increasedpistons;13.4,'-;:.

fil m ifim compressiv strensthtoi sup- Bay the attached to sa ene y 211 r-ash u rbutihave twor'hori- -=az mta y1diametrical; poppos d rally ircu ar i-earlike 1 portions -.-e.a.ch iadaptedfto be attached a to for cast-5 integral with ga'ithrust 1 bearing s'housing ,.;29 asimay:mostg-reaidilmbe:seeniimFig; l1. ."Gener ally centrally gilocated in oscillating yokes :58 Id -2 fit'here x-is-gnositioned a lug'ste extending fromqthe-jfaee rof the ::-main': portion of yokes 56 sand; 5 l aback in the idirectionv of compensating -.:w-eights- ;B.I. :EAbearingpinzfiltis' held in place vineeachtglugi lili.uandrpreferalsrly:afmetal sheathed rubber orwother type wO'f :r-resilient bushing '55 is fittedzaroundeach;bearing"-pina'e'lxto?form a-'bear 'caing withini-an;a perturenfi9 formed'near the end of .zieccentric 1-cranksl '49 wand 51 for that purpose.

. .s'tstu'dsir'lfleare formed I on :eachoscillating yoke T 150 rand-C5 vnearirthe periphery 0f the same and ranged ith their center on a circular circum- "tference. -Similar studs ll are formed on the face -01 :ea'oh -=compensating weight :6 I which "faces-its r espective oscillating yoke-"' and" 51 and eachis in line with a stud l0. The purpose of studs 10 'a-nd''|l*-.- as is'e-shown in Fig. 10- is to support the 1 series ofecompensating-compression springs -12 for ie'ach os'cillat'or-ybke50 'or 5l. The weight of weights -6I and the snumber -and stiffness of springs H -are chosen' with respect to the weight oi a -pair-of upper-rollers '20 and the'speed of 11 their reciprocation *to constitute a mechanically -balance'd"compensating system which when-the machine 'is *irroperationwillfbe 180 out offphase with the reciprocation "of its respective "pair of upper rollers.

"Referring-to *Fig! 5 it may be-seenthat one end of each *shaft *28 "of upper rollers '26 extends through a-n upper roller bearing housing 2B, which a asa above stated is mounted-upon bearing 1 block -21 --an'd terminates in its respective" thrust bearing housing 29. Bearing housings -26 en- -close a bearing'whichhasa number of ball races -13 heldin suitable ballraceguide "M. The halls of -races 'I3 bear upon bearing surface 15 keyed to bea1ing -housihg Z'G'andbearing sleeve lfi free to -revolve' on shaft 28. These bearings are thus designed to permit with I aminimum of friction longitudinal movement --as -well :as rotation of tsha'fts' ZB. *Ehrustbearing housings '29 enclose i'bearings designdto.permitfree rotation of shaft -28. They comprise two se'ts 01" shock mounted IOHBIiS'Y 'I l which are ot" *frusto -conical shape and which ibear 1 1113011 "bearing-surfaces "i9 keyed :to shatter. "Lockunuts 18.0 are =threaded son the :;endigof.;shajfts 28 tdhold'rthgfthrust bearing as- ESembHQSZiII-TDIZJQB.

g'lilurtherreference'zto ;'Fig.:5 'showstthe mountging'iof pneumaticgcylinders:35 .onzbearing blocks 2'.1 and -,'shows :shafts -:3| :of ;lower :rollers 2| extending through pokes 23.2 an-d having mounted :onitheir ends rgearszoriwheels '8! forlthe reception of driving chains or belts'fifi sarranged' as sshowniinzfifi ffl.

,rAsz-wa, ate abovegthezweightof.compensatting Eweightsx' li.I rand ;.thet-:number *andstiffness "of *springsilZ :arenhoserr with respect 'to' the weight :and 3813866. of a reciprocatory motion 1 of .-:a pair of upper rollers 20 to constitute a mechanically ibalanced'cornpensating system 180 but of phase with th'e areciprocation fof-iits rollers so that a minimumof vibration 'istransmitted'f-rom rollers 20-'to -frame 'FZZJa-IYd ot-her parts of "the machine.

Whenithe speed: of reciprocation of-npper rollers 7 29 is changed, the natural period of vibration of the compensating systems comprising weights BI and springs 12 must be changed. This can be accomplished by arranging springs 12 so that one or more of them may be readily removed. As is shown in Figs. 9 and 11, eight springs 12 may be used and, as is shown in Fig. 10, any of the eight may be readily removed by unscrewing respective stud 19 on oscillator yoke 50 and removing the spring. The actual number of springs 12 used for each oscillator yoke on a particular machine is not critical but should be chosen so that the removal of one or more alters the natural period of the compensating system to correspond to the desired and predetermined reduced speeds of reciprocation of upper rollers 20. However, the number of springs 72 for each oscillator yoke "59 or should be sufficient so that several of them can be removed without having an arc of over about 90 between any of the remaining springs.

Hydraulic couplings 45 are interposed in the driving train between motors 43 and eccentric cranks 49 or 5! to prevent any momentary shock and resultant injury to motors 43 particularly during the periods of starting and stopping the machine.

When the machine is in operation and motors 43 are started the reciprocation of upper rollers 29 will not come up to full speed immediately. During this period and up through the resonant point of the springs, instead of 180 out of phase with the reciprocating system, the compensating masses stay in phase with the motion of the rollers. Under short strokes the acceleration period is so brief that no difiiculty is experienced as in passing through this resonant period. At

longer strokes it is sometimes necessary to hold the weights in some manner until the rollers have reached full speed and then to release them. The compensating masses immediately take the opposite and compensating stroke to the rollers. When motors 43 are stopped, however, the mass of the pairs of upper rollers 29 is so great that it takes an appreciable length of time for them to stop reciprocating. During this time of deceleration, the system passes through the resonant period of the springs, at which point the load forces are at a maximum. Any prolonged period of this excessive vibration could result in damage to the machine. To prevent this, magnetic brakes 59 are mounted on shafts t8 and 56 and arranged to become operative when motors 43 are shut off in order to hasten the deceleration of the machine and thus cut down the length of time of the in-resonance period to a minimum.

Adjustments in the speed of rotation of lower rollers 2| are accomplished by adjusting the speed of motor 38 or other prime mover used for this purpose. Adjustments in the speed of reciprocation of upper rollers 20 may be accomplished by adjusting the speed of motors 43, the gear ratios of gear assemblies 46 and '54 or the ratio of the sprocket wheels or pulley for chain or belt drives 41 and 55.

The amplitude of the reciprocation of upper rollers 29 is dependent upon the throw of eccentrics 49 and 51 and, therefore, may be adjusted by changing the throw of those eccentrics 01' replacing them by other eccentrics having the desired throw.

The pressure exerted on the material F may be varied, as explained above, by changing the pressure of the fluid introduced intopressure chambers 42. An increase in pressure ofthis fluid increases the pressure on the material F.

It is further possible by proper connections and reducing valves (not shown) in a multiple unit machine to apply a different pressur on the material F when passing between the rollers of one unit than when passing between the rollers of the other units.

In order to grip aprons B or material F positively and to transmit efficiently to the material F the reciprocatory motion of upper rollers 20, both upper rollers 20 and lower rollers 2| have circumferential grooves cut in them. These grooves may be of the same shape for upper rollers 20 and lower rollers 21 and are shown at 82 in Fig. 8 for, by way of example, an upper roller 20. They may be milled or formed in any other suitable manner on the rollers but it is essential that the edges 83 formed at the surface of the rollers by the grooves be sharp in order to grip the apron B or material F in a positive and efiicient manner.

The mode of operation of a machine constructed in accordance with the present invention is best described by reference to Fig. 12. In the example represented by this figure the two batts are hardened at the same time, but it is to be understood that the machine may also be operated with only one batt or with a, larger number of batts than two such as six or eight. Further in the example represented by Fig. 12 only one apron B is used although, as stated above, in some instances it will be found desirable to use an apron both above and under the material F.

Apron B is a continuous apron which may be of any suitable material such as canvas or burlap which presents a sufiiciently rough surface to cause the batt to cling to it. Apron B passes around roller 84, over series of feed table rollers 85, under roller 86, over another series of feed table rollers 81, between upper rollers 29 and lower rollers 2|, over receiving table rollers 39, around roller 88 and back to roller 84. Power is applied to one or more receiving table rollers 39 and to lower rollers 2| as explained above. Rollers 84, 85, 81, 2|, 39, and 88 all rotate in a clockwise direction as viewed in Fig. 12. Roller 86 and upper rollers 20 rotate in a counter-clockwise direction as viewed in that figure. No direct power is applied to upper rollers 20, their rotation being caused by frictional drive from contact with the material F or an upper apron, if used. When necessary there may be added in any convenient place adjustable take-up rollers (not shown) to overcome any stretching of apron B. The same result may be accomplished by having either roller 84 or roller 88 mounted in its respective bearing so that it may be moved lengthwise of the machine so that the path of travel of apron B may be shortened or lengthened as desired.

One batt of the material F wound on roll 89 is placed on aprong B on feeding table 24 properly arranged and aligned so that the material will be unwound and travel along with apron B as it passes between upper rollers 20 and lower rollers 2|. The second batt of the material F wound on a roll 99 is also placed on apron B on feeding table 24 properly arranged and aligned so that the material will be unwound and will pass between upper rollers 20 and lower rollers 2|. Roll 9| carrying a separator cloth S is placed on aprong B between rolls 89 and 90 so that the separator cloth unwinds and is carried along on top of the material F that was wound on roll 89. After passing roll 99 there are nowon feed ta 4 s veralllayersiwhich;fromitheibottom to the topare apron B, materialF from roll89, separators. and material E, i'fom roll 90,-] They passbetweenil pper rollers 2'0 and lower rollers, 2 If in this arrangement.

Situated conveniently andbuilt into feedtable, 24 in any desired'manner 'is a steam bath 92. The above described layei'sw-alre' pulled through bath 92by reason of roller, low t ur ce ee-d5; 4, a, 92 may take any desired form into which steam is brought into contact with the material F.

After passing through steam bath 92 the layers travel over rollers 81 on feed table 24 and finally enter the main portion of the machine being drawn between upper rollers and lower rollers 2|. It is to be noted that since the axes of upper rollers 20 and lower rollers 2| are not in the same vertical planes that the layers in passing between them follow a wavy or sinuous path. When a machine comprises several units as in the embodiment described herein the above described layers pass from the first unit to the second and so on until they emerge on receiving table 25.

Receiving table 25 is equipped with rollers 39 over which apron B and the layers it carries are passed. Several wind-up rolls are placed on receiving table 25. In the present example roll 93, placed closest to the main part of the machine is arranged to wind up material F, now hardened, from feed roll 9|, roll 94 is arranged to wind up separator S and roll 95 is arranged to wind up material F, now hardened, from feed roll 89. Apron B as above stated, continues on around roller 88.

In the embodiment discussed above two batts of material are hardened at the same time. Should it be desired to harden more than two batts at the same time, additional feed rolls carrying batts and similar to rolls 89 and 90 are placed on feed table 24 with a roll for a separator cloth between each. Similar provision of additional wind-up rolls is made on receiving table 25. The important consideration is that the layers passing between upper rollers 20 and lower rollers 2| from the bottom up are apron, material, separator, material, and so on with a top apron, if used, on top.

We claim:

1. In a felt hardening machine a series of rollers having their axes substantially in a horizontal plane, means for moving said rollers back and forth along their respective axes, bearing means permitting the rotation of said rollers about their respective axes and holding said rollers against other horizontal and vertical movement, a second set of rollers having their axes substantially in a second horizontal plane disposed below the plane of said first series of rollers, means for rotating the rollers of said second set about their respective axes, bearing means for the rollers of said second set arranged to permit said rollers to rotate about their respective axes, vertically moveable yokes disposed to receive said latter bearing means, guide members fixedly attached to said machine and adapted to receive said yokes and to permit only vertical motion thereof and pneumatic means mounted on the frame of said machine for raising said yokes comprising a piston rod and piston attached to and extending upwardly from each of said yokes, a cylinder attached to said machine adapted to receive each of said pistons and a pressure chamer in each of said cylinders under said piston whereby when pressure is increased in said cylinitiwh is gree -ed. able lr- Steam bath derithecrollerssoft said first; series-and; the rollers of saidi second-- series can, be. drawn toward each no other movement of said rollers; within said;

bearings, yokes for supporting said latter bearings, guides mounted on the frame of said machine in which said yokes are received providing for vertical motion of said yokes but preventing any other motion of said yokes, pneumatic cylinders mounted on the frame of said machine, a piston disposed in each of said cylinders and for each of said yokes and connected to and extending upwardly from each of said yokes, a pressure chamber in each of said cylinders disposed below the piston therein whereby as the pressure is varied in said pneumatic cylinders said linkage moves said yokes up or down in said guides thus varying the pressure exerted on material between said rollers.

3. In a felt hardening machine, a plurality of upper rollers, a pair of bearings for each of said upper rollers permitting rotation of each of said rollers about its axis, means for reciprocating each of said upper rollers at a relatively high rate along a direction parallel to its respective axis, means associated with each pair of said bearings for permitting said reciprocation, a plurality of lower rollers, a pair of bearings for each of said lower rollers permitting rotation of each of said rollers about its axis but preventing any other motion of said lower rollers within their respective pairs of bearings, means comprising conveyor aprons for passing material to be hardened between said upper rollers and said lower rollers, means for fixedly mounting said bearings for said upper rollers on the frame of the machine, yokes for mounting said bearings for said lower rollers, vertical guideways fixedly mounted on the frame of said machine and adapted to receive said yokes, a piston rod and piston attached to and extending upwardly from each of said yokes and means mounted on the frame of said machine each comprising an enclosed cylinder adapted to receive a fiuid under pressure and to receive in slidable relation thereto said piston, means for introducing a fiuid under pressure to the portion of said cylinder below said piston whereby said yoke is used and whereby a lower roller is drawn upward and toward it respective upper roller thereby exerting pressure on said material as it passes between said rollers.

4. In a felt hardening machine having a plurality of upper rollers and a plurality of lower rollers wherein the vertical position of the upper rollers with respect to the body of said machine is fixed and the vertical position of the lower rollers with respect to the body of the machine may be altered, means for passing the material to be hardened between said rollers, means for preventing the substantial deviation of the axes of the lower rollers from the horizontal comprising a bearing for each end of each of said lower rollers, a yoke for supporting each of said bearings, a vertical extension on each of said yokes connected to a piston, a closed cylinder for each of said pistons forming inassociation therewith a pressure chamber between said piston and the lower wall of said cylinder, means for supplying fluid under pressure to each of said pressure chambers and means to insure equal pressure in the chambers for the yokes supporting the pressure bearings associated with each end of a roller.

RALPH I. ROBBINS. BELA FREYER.

REFERENCES CITED The following references are of record in the file of this patent:

Number ii UNITED STATES PATENTS Name Date Reyno1ds' Dec. 18, 1934 Casse Sept. 21, 1937 Slayter Dec. 28, 1948 Merchant Aug. 23, 1949 FOREIGN PATENTS Country Date Number Great Britain Nov. 18, 1937 

